Measuring device placement.

<p>Measuring device placement.</p

Block diagram of wireless data acquisition node.

<p>Block diagram of wireless data acquisition node.</p

Picture of wireless node.

<p>Picture of wireless node.</p

RSSI value of different places.

<p>RSSI value of different places.</p

Diagram of equivalent circuit model.

<p>Diagram of equivalent circuit model.</p

AD Command Response of Xbee Pro.

<p>AD Command Response of Xbee Pro.</p

Topology of three kinds of network.

<p>Topology of three kinds of network.</p

Framework of the space charge measurement.

<p>Framework of the space charge measurement.</p

Packet Loss Rate under Different Environment.

<p>Packet Loss Rate under Different Environment.</p

Structure of space charge density measurement instrument.

<p>Structure of space charge density measurement instrument.</p